vmscan: report vm_flags in page_referenced()

Collect vma->vm_flags of the VMAs that actually referenced the page.

This is preparing for more informed reclaim heuristics, eg.  to protect
executable file pages more aggressively.  For now only the VM_EXEC bit
will be used by the caller.

Thanks to Johannes, Peter and Minchan for all the good tips.

Acked-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index 619379a1dd98..216d024f830d 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -83,7 +83,8 @@ static inline void page_dup_rmap(struct page *page, struct vm_area_struct *vma,
 /*
  * Called from mm/vmscan.c to handle paging out
  */
-int page_referenced(struct page *, int is_locked, struct mem_cgroup *cnt);
+int page_referenced(struct page *, int is_locked,
+                        struct mem_cgroup *cnt, unsigned long *vm_flags);
 int try_to_unmap(struct page *, int ignore_refs);
 
 /*
@@ -117,7 +118,7 @@ int try_to_munlock(struct page *);
 #define anon_vma_prepare(vma)   (0)
 #define anon_vma_link(vma)      do {} while (0)
 
-#define page_referenced(page,l,cnt) TestClearPageReferenced(page)
+#define page_referenced(page, locked, cnt, flags) TestClearPageReferenced(page)
 #define try_to_unmap(page, refs) SWAP_FAIL
 
 static inline int page_mkclean(struct page *page)